US 7,485,336 B2
Method for predicting and optimizing chip performance in cured thermoset coatings
Timothy S. December, Rochester Hills, Mich. (US); Marc Bennett Fenwick, Commerce Township, Mich. (US); Yoshiko Kobayashi-San, Ann Arbor, Mich. (US); Scott Kubish, Michigan, Mich. (US); JoAnn Lanza, Farmington Hills, Mich. (US); and Ippei Shinohara, Novi, Mich. (US)
Assigned to BASF Corporation, Florham Park, N.J. (US); and Toyota Motor Engineering & Manufacturing North America, Inc., Ann Arbor, Mich. (US)
Filed on Apr. 14, 2005, as Appl. No. 11/106,284.
Prior Publication US 2006/0234404 A1, Oct. 19, 2006
Int. Cl. B05D 5/00 (2006.01)
U.S. Cl. 427—8  [427/407.1; 427/409] 19 Claims
 
1. A single measurement method of predicting chip performance of a cured coating system comprising a first coating composition, comprising
providing a coated substrate comprising a substrate and a cured film of the first coating composition thereon,
measuring elastic work energy (We/Wtot) of the cured film, and
calculating a % C.P. of the coated substrate via the formula:
% C.P.=7.61636−0.225473(We/Wtot)
wherein a 5 C.P. of no more than about 3.50% correlates to a total paint loss of no more than 5% of a coating system comprising the first coating composition.